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81.
Nasanjargal Purev Ladislav Burgert Petr Prichystal Radim Hrdina Jiri Kühn Michal Cerny Jamyan Oyuntulkhuur 《Coloration Technology》2013,129(6):412-417
CI Acid Black 210 was microencapsulated into liposomic systems, and the effects of the microencapsulation on dyebath exhaustion, depth of shade, colour fastness properties and through‐dyeing of chrome‐tanned leather were studied. In comparison with the original dyestuff form, the microencapsulated dye showed a deeper shade and a greater depth of through‐dyeing. Exhaustion and colour fastness values were the same. 相似文献
82.
Traveling-wave Phenomena in a Model of Autocrine Signaling Coupled with Dynamics of the MAPK Cascade
Recently we have revealed a minimal reaction subnetwork in the MAPK (mitogen-activated protein kinase) cascade that is responsible for the emergence of bistable and oscillatory behavior. Here we examine a possible mechanism that provides for the propagation of increased MAPK activity in cell populations by interconnecting the intracellular MAPK subnetwork with the ligand-receptor signaling machinery. Such approach allows for significant reduction of the dimensionality of the parameter space on one hand and the conservation of dynamical complexity of the system on the other hand. The coupled model predicts coexistence of one, two or three different stable steady states, or the coexistence of a stable steady state and periodic solution. We found two robust and physiologically relevant characteristics of the proposed model: (i) There is a very large region of coexistence of at least one stable steady state with non-zero MAPK activity and one steady state with zero MAPK activity in the parameter space. (ii) Spontaneous traveling front waves always switching originally inactive cells into ligand releasing cells emerge in adjacent cell populations, e. g. in healthy and injured tissues. Moreover, the formation of composite traveling front waves and spatial oscillatory patterns of MAPK activity are predicted and discussed. 相似文献
83.
84.
Atomic force microscopy (AFM) has been used to study the effect of various photoinitiators doped into poly(methyl methacrylate)
(PMMA) on the mechanical properties of PMMA films at the nanometer scale. Pure and modified PMMA films (containing four different
photoinitiators) were exposed to a mercury vapor lamp in air atmosphere. Force–distance curves for hardness, Young modulus,
and adhesion forces were obtained using different AFM modes (tapping or contact-mode) and different tips (diamond or silicon
nitride). The results revealed that the added photoinitiators slightly changed the nanomechanical properties of PMMA as a
result of alterations in the photochemical reactions and physical processes occurring in the studied systems. tert-Butyl peroxybenzoate had the most efficient effect on the measured parameters in UV-irradiated PMMA, whereas benzoyl peroxide
was less active. The mechanism of the observed processes is discussed. 相似文献
85.
Frydrychowski AF Gumiński W Rojewski M Kaczmarek J Juzwa W 《IEEE transactions on bio-medical engineering》2002,49(8):887-904
This paper presents technical foundations for a new technique of near-infrared transillumination-backscattering sounding, which is designed to enable noninvasive detection and monitoring of changes in the width of the subarachnoid space (SAS) and magnitude of cerebrovascular pulsation in humans. The key novelty of the technique is elimination of influence of blood flow in the scalp on the signals received from two infrared sensors-proximal and distal. A dedicated digital algorithm is used to estimate on line the ratio of the powers of received signals, referred to as two-sensor distal-to-proximal received power quotient, TQ (t). The propagation duct for NIR radiation reaching the distal sensor is the SAS filled with translucent cerebrospinal fluid. Information on slow fluctuations of the average width of the SAS is contained in the slow-variable part of the TQ (t), called the subcardiac component, and in TQ itself. Variations in frequency and magnitude of faster oscillations of the width of that space around the baseline value, dependent on cerebrovascular pulsation, are reflected in instantaneous frequency and envelope of the fast-variable component. Frequency and magnitude of the cerebrovascular pulsation depend on the action of the heart, so this fast-variable component is referred to as the cardiac component. 相似文献
86.
Partition coefficients of phenol, salicylic acid, and several environmentally important chloro- and nitrophenols in a supercritical CO2-water system were measured using direct cocurrent extraction of aqueous solutions of the individual solutes with CO2. Partitioning data on the nitrophenols and salicylic acid were obtained for the first time. To bypass the troublesome and error-prone analysis of the CO2-rich phase, the present method employed only the solute concentrations in the aqueous phase before and after extraction to determine the partition coefficient. Unlike most previous engineering studies of phenol partitioning in a CO2-water system, the concentrations of phenolic solutes approached infinite dilution in both phases. This makes the results relevant to analytical-scale SFE of environmental water samples with CO2. Because of effective infinite dilution of the solutes, the partition coefficients provide a direct measure of relative CO2-philicity/hydrophilicity of the individual phenols. Compared to the octanol-water partition coefficients of substituted phenols, the CO2-water partition coefficients are more sensitive to substitution in the position neighboring the hydroxyl group. 相似文献
87.
Srivastava Shekhar Agrawal Gaurav Pioro Michal Medhi Deep 《Network and Service Management, IEEE Transactions on》2005,2(1):9-18
An important traffic engineering problem for OSPF networks is the determination of optimal link weights. Certainly, this depends on the traffic engineering objective. Regardless, often a variety of performance measures may be of interest to a network provider due to their impact on the network. In this paper, we consider different objectives and discuss how they impact the determination of the link weights and different performance measures. In particular, we propose a composite objective function; furthermore, we present a Lagrangian relaxation-based dual approach to determine the link weight system. We then consider different performance measures and discuss the effectiveness of different objectives through computational studies of a variety of network topologies. We find that our proposed composite objective function with Lagrangian relaxation-based dual approach is very effective in meeting different performance measures and is computationally very fast. 相似文献
88.
Andrzej Buller Michal Joachimczak Juan Liu Katsunori Shimohara 《Artificial Life and Robotics》2005,9(4):197-201
This article presents the key assumptions and current status of the ATR Artificial Brain Project being undertaken to create
Volitron, a device equipped with circuitry that enables the emergence of thought. Such thought would be recognized from Volitron's
specific communication behaviors. The project consists of three complementary themes: psychodynamic architecture, brain-specific
evolvable hardware, and the management of brain-building. The psychodynamic architecture is designed to develop automatically,
driven by “pleasure” coming from discharges of tension gathered in special tension-accumulating devices. Tension-discharging
patterns come first of all from the robot's interactions with its care giver/provider. For the dedicated hardware, we developed
qcellular-automata (qCA), in which groups of uniform logic primitives (q-cells) serve as spike-train-processing units, as well as pulsed para-neural networks (PPNN) that can be evolved, using fuzzified
signals and a genetic algorithm combined with hill climbing, and converted into qCA. The psychodynamic ideas were tested using three robots: Neko, equipped with a pleasure-driven associator, Miao, equipped with MemeStorms (a special working memory in which conflicting ideas fight for access to the long-term memory and
actuators), and Miao+, whose brain is equipped with a growing neural network.
This work was presented in part at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30,
2004 相似文献
89.
The so-called permutation separability criteria are simple operational conditions that are necessary for separability of mixed
states of multipartite systems: (1) permute the indices of the density matrix and (2) check if the trace norm of at least
one of the resulting operators is greater than one. If it is greater than one then the state is necessarily entangled. A shortcoming
of the permutation separability criteria is that many permutations give rise to equivalent separability criteria. Therefore,
we introduce a necessary condition for two permutations to yield independent criteria called combinatorial independence. This
condition basically means that the map corresponding to one permutation cannot be obtained by concatenating the map corresponding
to the second permutation with a norm-preserving map. We characterize completely combina-torially independent criteria, and
determine simple permutations that represent all independent criteria. The representatives can be visualized by means of a
simple graphical notation. They are composed of three basic operations: partial transpose, and two types of so-called reshufflings.
In particular, for a four-partite system all criteria except one are composed of partial transpose and only one type of reshuffling;
the exceptional one requires the second type of reshuffling. Furthermore, we show how to obtain efficiently a simple representative
for every permutation. This method allows to check easily if two permutations are Combinatorially equivalent or not. 相似文献
90.
When a rigid scene is imaged by a moving camera, the set of all displacements of all points across multiple frames often resides in a low-dimensional linear subspace. Linear subspace constraints have been used successfully in the past for recovering 3D structure and 3D motion information from multiple frames (e.g., by using the factorization method of Tomasi and Kanade (1992, International Journal of Computer Vision, 9:137–154)). These methods assume that the 2D correspondences have been precomputed. However, correspondence estimation is a fundamental problem in motion analysis. In this paper we show how the multi-frame subspace constraints can be used for constraining the 2D correspondence estimation process itself.We show that the multi-frame subspace constraints are valid not only for affine cameras, but also for a variety of imaging models, scene models, and motion models. The multi-frame subspace constraints are first translated from constraints on correspondences to constraints directly on image measurements (e.g., image brightness quantities). These brightness-based subspace constraints are then used for estimating the correspondences, by requiring that all corresponding points across all video frames reside in the appropriate low-dimensional linear subspace.The multi-frame subspace constraints are geometrically meaningful, and are {not} violated at depth discontinuities, nor when the camera-motion changes abruptly. These constraints can therefore replace {heuristic} constraints commonly used in optical-flow estimation, such as spatial or temporal smoothness. 相似文献